Recent releveling measurements conducted by the National Geodetic Survey in West Texas and southeastern New Mexico indicate uplift of the Diablo Plateau-Salt Basin region relative to benchmarks to the northeast in the Great Plains. These new measurements confirm and enhance the previously reported interpretation of releveling data in this area. Total relative uplift measured between 1934 and 1977 reaches 19¿3 cm. Combining this new information with leveling data from 1934, 1943 and 1958 along this same route indicates that: (1) the uplifted area extends 120 km in the east-west direction (there is presently no control on any north-south component of tilting), with maximum relative uplift occurring approcimately 12 km west of the boundary between the Diablo Plateau and Salt Basin graben; and (2) on the time scale between measurements (~20 yrs), uplift appears to be occurring more or less continuously, although not at a constant rate. The progressive deformation indicated by the releveling measurements, the large magnitude relative to possible leveling errors, and the spatial dimensions of the uplift rule out systematic errors or near-surface effects (water table variations, sediment compaction, etc.) as an explanation and favor a tectonic origin. Intrucrustal magnetic activity or some form of preseismic deformation (dilatancy, fault creep at depth, etc.) appear to be the most reasonable explanations in view of presently available geologic and goephysical information. The pattern of uparching is perturbed at the Salt Basin graben, indicating 4.2¿0.3 cm of subsidence relative to its margins between 1958 and 1977. This subsidence could be related to the regional tectonic uparching, although near-surface, non-tectonic effects cannot be excluded.